Apple plans to more than double the amount of fuel cells used to generate electricity at its $1 billion data center in Maiden, North Carolina to 10 megawatts, surpassing eBay to become the largest such project in the U.S. not owned by a utility.

Apple filed a request with the North Carolina Utilities Commission to increase the size of its fuel cell farm from 4.8 MW to 10 MW, news first reported by The Charlotte Observer. Apple began the start-up and testing of the fuel cells in October 2012, according to filings with NCUC. Apple said in the filing it anticipates the 10 MW facility will be online by January 2013.

Here's one interesting note: Apple's biogas fuel cells won't necessarily be used to provide power to its data center. In the filing with NCUC, Apple indicates it will sell power generated by the fuel cells to Duke Energy.

The fuel cells, provided by Bloom Energy, will run on directed biogas. Element Markets Renewable Energy will supply the directed biogas, which will be produced from landfill methane, according to the filings with NCUC.

Bloom Energy also is providing fuel cells to help power the next phase of eBay's flagship data center in Utah.

Bloom Energy makes solid oxide fuel cells, which are assembled by the thousands into an energy server or Bloom box. The parking space-size Bloom box converts fuel like natural gas or biogas into electricity. The 6-MW fuel cell installation at eBay’s data center uses biogas. Bloom Energy installed a 500-kilowatt fuel cell system that uses biogas at eBay’s headquarters in San Jose, Calif., in 2010.

Kirsten Korosec has written for Technology Review, Marketing News, The Hill, BNET and Bloomberg News. She holds a degree from Northwestern University's Medill School of Journalism. She is based in Tucson, Arizona.
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